Device and method of displaying images

ABSTRACT

A method for censoring inappropriate images during a video call is disclosed. The method includes: receiving, from a first terminal, a stream including a plurality of images captured by the first terminal; attempting to detect a face in each of one or more sample images selected among the plurality of images included in the stream; determining that the face has not been detected in at least some of the sample images; performing image processing on at least one of the plurality of images included in the stream; and displaying the plurality of images included in the stream.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2016-0130656, filed on Oct. 10, 2016, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND 1. Field

One or more embodiments relate to an image display device and an image display method, which are capable of preventing a user who makes a video call with a counterpart from being exposed to inappropriate images.

2. Description of the Related Art

With the developments of communication technologies and the miniaturization of electronic devices, personal terminals have become widely spread to general customers. In particular, personal portable terminals, such as smart phones or smart tablets, have recently been widely used. Most terminals include a communication function. A user may search on the Internet using a terminal or may exchange messages with another user.

Also, with the developments of small-sized camera technologies, small-sized microphone technologies, small-sized display technologies, and small-sized speaker technologies, most terminals such as smart phones include a camera, a microphone, a display, and a speaker. A user may use the terminal to record a voice or capture a video including a voice. The user may confirm the recorded voice through the speaker included in the terminal or the captured video through the display included in the terminal.

Also, the user may share the recorded voice or the captured video with another user using the communication function of the terminal. The user may send a previously recorded voice or a previously captured video to another user. Also, the user may send a voice or a video, which is being currently recorded or captured by the terminal, to another user in real time.

Also, at the same time, another user may send a voice or a video, which is being currently recorded or captured by his or her own terminal, to the user in real time. The display included in the terminal of the user may simultaneously display the video that is being currently captured by the terminal of the user and the video that is being currently captured by the terminal of another user. Also, the speaker included in the terminal of the user may simultaneously reproduce the voice that is being currently recorded by the terminal of another user. In other words, the user and another user may make a video call to each other using their own terminals.

The user and another user may or may not be acquainted with each other. A plurality of terminals, including the terminal of the user and the terminal of another user, may be connected to a server. The server may mediate between the terminal of the user and the terminal of another user. Therefore, even though the user and another user are not acquainted with each other, the user and another user may make a video call to each other through the mediation of the server.

When the user makes a video call with the counterpart, the user may be exposed to obscene images from the counterpart. In particular, when the user makes a video call with an unacquainted counterpart, it is highly likely that the user will be exposed to obscene images from the counterpart.

For example, a terminal of the user may receive a naked body image of the counterpart, which is captured by a terminal of the counterpart, through a video call session. The terminal of the user displays the received image and thus the user may be exposed to the obscene image. If the user is exposed to the obscene image that the user does not want, the user may feel sexual shame or discomfort.

SUMMARY

Some example embodiments may provide an image display apparatus and an image display method, which are capable of preventing a user who makes a video call with a counterpart from being exposed to obscene images from the counterpart.

Some example embodiments may provide an image display device and an image display method, which are capable of preventing a user who makes a video call with a counterpart from sexual shame or discomfort that the user may feel from images from the counterpart.

Some example embodiments may provide an image display device and an image display method, which are capable of guiding a proper video call between users.

Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments.

In some example embodiments, an image display method may comprise: receiving, from a first terminal, a stream including a plurality of images captured by the first terminal; attempting to detect a face in each of one or more sample images selected among the plurality of images included in the stream; determining that the face has not been detected in at least some of the sample images; performing image processing on at least one of the plurality of images included in the stream; and displaying the plurality of images included in the stream.

In some example embodiments, the performing of the image processing may comprise: selecting one or more target images among the plurality of images included in the stream; selecting a target region of at least a portion of each of the target images; and performing the image processing on the selected target region of each of the target images.

In some example embodiments, the attempting to detect the face may comprise: selecting one or more sample images corresponding to a recent specific time among the plurality of images included in the stream; and attempting to detect the face in the selected one or more sample images. The determining that the face has not been detected may include determining that the face has not been detected in the selected one or more sample images.

In some example embodiments, the selecting of the one or more target images may include selecting, as the target images, entire images corresponding to the recent specific time among the plurality of images included in the stream.

In some example embodiments, the attempting to detect the face may comprise: selecting a new sample image among newly received images in the stream at each specific period; and attempting to detect the face in the new sample image whenever the new sample image is selected. The determining that the face has not been detected may include determining that the face has not been detected in entire sample images selected within the recent specific time among the sample images.

In some example embodiments, the selecting of the one or more target images may include selecting, as the target images, entire images corresponding to the recent specific time among the plurality of images included in the stream.

In some example embodiments, the attempting to detect the face may comprise: attempting to detect the face in a first sample image selected among the plurality of images included in the stream; and attempting to detect the face in each of one or more second sample images selected among entire images received later than the first sample image in the stream. The determining that the face has not been detected may include determining that the face has not been detected in the first sample image and the entire one or more second samples.

In some example embodiments, the selecting of the one or more target images may include selecting, as the target images, the first sample image and the entire images received later than the first sample image among the plurality of images included in the stream.

In some example embodiments, the selecting of the one or more target images may include selecting, as the target images, the first sample image, the one or more second sample images, and entire images received later than the first sample image and received earlier than a last received image of the one or more second sample images among the plurality of images included in the stream.

In some example embodiments, the attempting to detect the face may comprise: selecting two or more sample images among the plurality of images included in the stream, the two or more sample images including a first sample image corresponding to a first time point and a second sample image corresponding to a second time point having a time difference from the first time point by a specific time or more; and attempting to detect the face in each of the selected two or more sample images. The determining that the face has not been detected may include determining that the face has not been detected in the first sample image, the second sample image, and entire sample images corresponding to the time from the first time point to the second time point among the selected at least two sample images.

In some example embodiments, the selecting of the one or more target images may include selecting, as the target images, the entire images corresponding to the time from the first time point to the second time point among the plurality of images included in the stream.

In some example embodiments, the selecting of the one or more target images may include selecting, as the target images, one or more images corresponding to the at least some of the sample images in which the face has not been detected among the plurality of images included in the stream, or all of the plurality of images.

In some example embodiments, the selecting of the target region of at least the portion of each of the target images may include selecting, as the target region, a region corresponding to a skin color in the target image, or an entire region of the target image.

In some example embodiments, the performing of the image processing on the selected target region of each of the target images may include deleting the target region, applying a blur effect or a mosaic effect to the target region, adjusting a color, a brightness, a contrast, or a saturation of the target region, or substituting the target region with another image.

In some example embodiments, the image display method may further comprise: receiving a request for cancelling the image processing; and displaying an image received after the reception of the request among the plurality of images included in the stream, without the image processing.

In some example embodiments, an image display method may comprise: establishing a video call session with a first terminal; receiving a stream, which includes a plurality of images captured by the first terminal, through the video call session; displaying the plurality of images included in the stream; attempting to detect a face in each of one or more sample images selected among the plurality of images included in the stream; determining that the face has not been detected in at least some of the sample images; and terminating the video call session.

In some example embodiments, an image display apparatus may comprise: a communication interface configured to receive, from a first terminal, a stream including a plurality of images captured by the first terminal; an output interface configured to display the plurality of images included in the stream; and a controller configured to attempt to detect a face in each of one or more sample images selected among the plurality of images included in the stream. The controller may determine that the face has not been detected in at least some of the sample images. The controller may perform image processing on one or more images among the plurality of images. The output interface may display the one or more images on which the image processing has been performed.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readily appreciated from the following description of embodiments, taken in conjunction with the accompanying drawings in which:

FIG. 1 is a network configuration diagram illustrating an environment in which an image display device according to an embodiment operates;

FIG. 2 is a block diagram of an image display device according to an embodiment;

FIG. 3 is a flowchart of an image display method according to an embodiment;

FIG. 4 illustrates a sample image selected among a plurality of images included in a stream, according to an embodiment;

FIG. 5 illustrates another sample image selected among a plurality of images included in a stream, according to an embodiment;

FIG. 6 is a flowchart of a process of processing an image, according to an embodiment;

FIG. 7 is a flowchart of a process of attempting to detect a face to a process of selecting a target image, according to an embodiment;

FIG. 8 is a reference diagram for describing a process of selecting a sample image, according to an embodiment;

FIG. 9 is a flowchart of a process of attempting to detect a face to a process of selecting a target image, according to another embodiment;

FIG. 10 is a flowchart of a process of attempting to detect a face to a process of selecting a target image, according to another embodiment;

FIG. 11 is a reference diagram for describing a process of selecting a sample image, according to another embodiment;

FIG. 12 is a flowchart of a process of attempting to detect a face to a process of selecting a target image, according to another embodiment;

FIG. 13 is a reference diagram illustrating a selected target region according to an embodiment;

FIG. 14 is a reference diagram illustrating a selected target region according to another embodiment;

FIG. 15 is a reference diagram illustrating a selected target region according to another embodiment;

FIG. 16 illustrates an image, on which image processing has been performed, according to an embodiment;

FIG. 17 illustrates an image, on which image processing has been performed, according to another embodiment;

FIG. 18 illustrates an image, on which image processing has been performed, according to another embodiment;

FIG. 19 illustrates an image, on which image processing has been performed, according to another embodiment; and

FIG. 20 is a flowchart of an image display method according to another embodiment.

DETAILED DESCRIPTION

Advantages and features and a method of achieving the same will be more clearly understood from embodiments described below in detail with reference to the accompanying drawings. However, the present disclosure is not limited to the following embodiments and may be implemented in various different forms. Embodiments are provided merely to complete disclosure and to provide those of ordinary skill in the art with the category of the present disclosure. The present disclosure is defined only by the claims. Wherever possible, the same reference numbers will be used throughout the specification to refer to the same or like components.

Also, it will be understood that although the terms “first”, “second”, etc. may be used herein to describe various components, these components should not be limited by these terms. These terms are only used to distinguish one component from another. Therefore, a first component used herein may be a second component within the technical scope of the present disclosure.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present disclosure. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated components and/or steps, but do not preclude the presence or addition of one or more other components and/or steps.

Unless otherwise defined, all terms used herein have the same meaning as commonly understood by those of ordinary skill in the art. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Hereinafter, terminals 100 and 150 and methods of controlling the same, according to embodiments, will be described in detail with reference to FIGS. 1 to 13.

Hereinafter, image display devices 100 and 150 and image display methods, according to embodiments, will be described in detail with reference to FIGS. 1 to 20.

FIG. 1 is a network configuration diagram illustrating an environment in which image display devices 100 and 150 according to an embodiment operate. Referring to FIG. 1, the environment in which the image display devices 100 and 150 operate may include a first image display device 100, and a second image display device 150 connected to the first image display device 100.

According to another embodiment, the environment in which the image display devices 100 and 150 operate may further include a server 200 connected to the first image display device 100 or the second image display device 150. The environment in which the image display devices 100 and 150 operate may not include the server 200.

The first image display device 100 may be a terminal. For convenience of description, the first image display device 100 and the first terminal 100 are interchangeably used herein.

The first terminal 100 may be, for example, a desktop computer, a laptop computer, a smart phone, a smart tablet, a smart watch, a mobile terminal, a digital camera, a wearable device, or a portable electronic device. The first terminal 100 may execute programs or applications.

The first terminal 100 may be connected to a communication network. The first terminal 100 may be connected to an external device via the communication network. The first terminal 100 may transmit data to the connected external device or receive data from the connected external device.

The communication network connected to the first terminal 100 may include a wired communication network, a wireless communication network, or a composite communication network. The communication network may include a mobile communication network such as 3G, Long Term Evolution (LTE), or LTE-A. The communication network may include a wired or wireless communication network such as Wi-Fi, Universal Mobile Telephone System/General Packet Radio Service (UMTS/GPRS), or Ethernet. The communication network may include a short-range communication network such as Magnetic Secure Transmission (MST), Radio Frequency IDentification (RFID), Near Field Communication (NFC), ZigBee, Z-Wave, Bluetooth, Bluetooth Low Energy (BLE), or InfraRed (IR) communication. The communication network may include Local Area Network (LAN), Metropolitan Area Network (MAN), or Wide Area Network (WAN).

FIG. 2 is a block diagram illustrating the configurations of the image display devices 100 and 150 according to an embodiment. Referring to FIG. 2, each of the image display devices 100 and 150 according to an embodiment may include an input interface 101, a controller 102, a storage 103, a communication interface 104, and an output interface 105.

The input interface 101 may receive an external signal. The input interface 101 may receive signals from users of the image display devices 100 and 150. Also, the input interface 101 may receive a signal from an external device. The input interface 101 may include, for example, a microphone, a camera, a keyboard, a mouse, a track ball, a touch screen, a button, a switch, a sensor, a network interface, or other input devices.

The input interface 101 may receive light from the exterior through the camera included in the input interface 101. The input interface 101 may receive light emitted from an external object or light reflected from an external object. The input interface 101 may capture images of the users of the image display devices 100 and 150 through the camera.

The input interface 101 may receive a voice from the exterior through the microphone included in the input interface 101. The input interface 101 may receive voices from the users of the image display devices 100 and 150. Also, the input interface 101 may receive voices from an external voice reproduction device. The input interface 101 may record voices of the users of the image display devices 100 and 150 through the microphone.

The controller 102 may control operations of the image display devices 100 and 150. The controller 102 may be connected to the components included in the image display devices 100 and 150. The controller 102 may control operations of the components included in the image display devices 100 and 150.

The controller 102 may process a signal. The controller 102 may process a signal received by the input interface 101. For example, the controller 102 may process a user's request received through the input interface 101. The controller 102 may process an image of a user captured by the camera included in the input interface 101. The controller 102 may process a user's voice recorded by the microphone included in the input interface 101.

The controller 102 may process a signal received by the communication interface 104. For example, the controller 102 may process a user's request received through the communication interface 104. The controller 102 may process an image or voice of another user received through the communication interface 104.

The controller 102 may control the operations of the image display devices 100 and 150 in response to a signal received by the input interface 101. The controller 102 may control the operations of the image display devices 100 and 150 in response to a user's request received through the input interface 101.

The controller 102 may perform an arithmetic operation. The controller 102 may perform an arithmetic operation according to a signal received by the input interface 101. The controller 102 may perform an arithmetic operation using a signal received by the input interface 101 or data stored in the storage 103. For example, the controller 102 may encode an image captured by the camera included in the input interface 101. The controller 102 may encode a voice recorded by the microphone included in the input interface 101.

The controller 102 may decode an image or voice of another user received through the communication interface 104. The controller 130 may perform postprocessing on the decoded image or voice. For example, the controller 102 may perform image processing on an image of another user received through the communication interface 104.

The controller 102 may perform control such that the result of the arithmetic operation is stored in the storage 103. The controller 102 may perform control such that the result of the arithmetic operation is output by the output interface 105.

The controller 102 may include, for example, a central processing unit (CPU), a graphic processing unit (GPU), a micro controller unit (MCU), or a microprocessor.

The storage 103 may store data. The storage 103 may store data to be used when the controller 102 performs the arithmetic operation. The storage 103 may store the result of the arithmetic operation performed by the controller 102. For example, the storage 103 may store an image or a voice encoded by the controller 102. The storage 103 may store data to be transmitted to the exterior through the communication interface 104, or may store data received from the exterior through the communication interface 104.

The storage 103 may include a volatile memory or a non-volatile memory. The storage 103 may include, for example, flash memory, read-only memory (ROM), random access memory (RAM), electrically erasable read-only memory (EEROM), erasable programmable read-only memory (EPROM), electrically erasable and programmable read-only memory (EEPROM), hard disk drive (HDD), register, or the like. The storage 103 may include, for example, a file system, a database, or an embedded database.

The communication interface 104 may transmit data to the exterior or receive data from the exterior. The communication interface 104 may transmit data to another image display terminal 100 or 150 or the server 200. The communication interface 104 may transmit data to another image display device 100 or 150 or the server 200. The communication interface 104 may transmit the result of the arithmetic operation performed by the controller 102 to the exterior. Also, the communication interface 104 may transmit data stored in the storage 103 to the exterior. The communication interface 104 may receive external data to be used when the controller 102 performs the arithmetic operation.

Data to be transmitted by the communication interface 104 or data received by the communication interface 104 may be stored in the storage 103. For example, the communication interface 104 may transmit an encoded image or voice stored in the storage 103 to the server 200 or another image display device 100 or 150. Also, the communication interface 104 may receive an image or a voice encoded by another terminal 100 or 150 from another terminal 100 or 150.

The communication interface 104 may include a long-range network interface such as a 3G module, an LTE module, an LTE-A module, a Wi-Fi module, a WiGig module, an Ultra Wide Band (UWB) module, or a LAN card. Also, the communication interface 104 may include a short-range network interface such as an MST module, a Bluetooth module, an NFC module, an RFID module, a ZigBee module, a Z-Wave module, or an IR module. In addition, the communication interface 104 may include other network interfaces.

The output interface 105 may output a signal to the exterior. The output interface 105 may, for example, display a screen, reproduce a sound, or output a vibration. The output interface 105 may include a display, a speaker, a vibrator, an oscillator, or other output devices.

The output interface 105 may display a screen. The controller 102 may control the output interface 105 to display a screen. The output interface 105 may display a user interface. The output interface 105 may display another screen in response to a user input.

The output interface 105 may display data. The output interface 105 may display the result of the arithmetic operation performed by the controller 102. The output interface 105 may display data stored in the storage 103. The output interface 105 may display data received by the communication interface 104.

The output interface 105 may include a flat-panel display device such as a liquid crystal display (LCD), an organic light-emitting diode (OLED), or a plasma display panel (PDP). The output interface 105 may include a curved display or a flexible display. The output interface 105 may include a touch screen.

The output interface 105 may display the image of the user captured by the first image display device 100 or the image of another user captured by the second image display device 150. Also, the output interface 105 may reproduce the voice of the user recorded by the first image display device 100 or the voice of another user captured by the second image display device 150.

The second image display device 150 may be a terminal. For convenience of description, the second image display device 150 and the second terminal 150 are interchangeably used herein.

A type of the second terminal 150 may be identical to or different from a type of the first terminal 100. The second terminal 150 may execute programs or applications.

The second terminal 150 may be connected to a communication network. The second terminal 150 may be connected to an external device via the communication network. The second terminal 150 may transmit data to the connected external device or receive data from the connected external device.

The second terminal 150 may be connected to the first terminal 100. The second terminal 150 may be connected to the first terminal 100 via the communication network. The second terminal 150 may transmit data to the first terminal 100 or receive data from the first terminal 100.

The first terminal 100 and the second terminal 150, which are connected to each other, may exchange messages, files, voice data, images, or videos with each other. The second terminal 150 may establish a voice call session or a video call session with the first terminal 100. The video call session may be established using, for example, Transmission Control Protocol (TCR), User Datagram Protocol (UDP), or Web Real-Time Communication (WebRTC). The user of the first terminal 100 and the user of the second terminal 150 may make a voice call or a video call with each other.

The video call session may be directly established between the first terminal 100 and the second terminal 150. According to another embodiment, the video call session may be established between the first terminal 100 and the second terminal 150 via at least one device. For example, the video call session may include a session established between the first terminal 100 and the server 200 and a session established between the server 200 and the second terminal 150.

The first terminal 100 and the second terminal 150 may directly exchange data with each other. Also, the first terminal 100 and the second terminal 150 may exchange data with each other via the server 200 or another mediating device.

The server 200 may be connected to the first terminal 100 or the second terminal 150. When the server 200 is connected to the first terminal 100, the server 200 may exchange data with the first terminal 100 via the communication network. When the server 200 is connected to the second terminal 150, the server 200 may exchange data with the second terminal 150 via the communication network.

The server 200 may receive data from the first terminals 100. The server 200 may perform an arithmetic operation using the data received from the first terminal 100. The server 200 may transmit the result of the arithmetic operation to the first terminal 100 or the second terminal 150. The server 200 may receive data from the second terminals 150. The server 200 may perform an arithmetic operation using the data received from the second terminal 150. The server 200 may transmit the result of the arithmetic operation to the first terminal 100 or the second terminal 150.

Hereinafter, specific operations of the image display devices 100 and 150, which perform image display methods, according to an embodiment will be described in detail with reference to FIGS. 3 to 20.

FIG. 3 is a flowchart of an image display method according to an embodiment. Referring to FIG. 3, in operation S100, a stream including a plurality of images captured by the first terminal 100 may be received from the first terminal 100.

The communication interface 104 of the second terminal 150 may establish a video call session with the first terminal 100. The communication interface 104 of the second terminal 150 may receive the stream from the first terminal 100 through the video call session. The stream may include a plurality of images. For example, the stream may include a video or at least two still images.

The plurality of images included in the stream may be images captured by the camera included in the input interface 101 of the first terminal 100. The second terminal 150 may continuously receive a plurality of images, which are being continuously captured by the first terminal 100, through the stream.

The plurality of images may be images of the user of the first terminal 100. For example, the plurality of images may include an image of a face of the user of the first terminal 100. The plurality of images may be an image of a body of the user of the first terminal 100.

The second terminal 150 may directly receive the stream from the first terminal 100. According to another embodiment, the second terminal 150 may receive the stream from the first terminal 100 via the server 200.

In operation S110, face detection may be attempted in each of one or more sample images selected among the plurality of images included in the stream. The controller 102 of the second terminal 150 may select one or more sample images among the plurality of images included in the stream. The controller 102 of the second terminal 150 may select a sample image among the plurality of images randomly or according to a specific rule.

For example, the controller 102 of the second terminal 150 may select a new sample image among newly received images in the stream at each specific period. The controller 102 of the second terminal 150 may select a new sample image among the entire images received later than the most recently selected sample image in the stream. The controller 102 of the second terminal 150 may select the new sample image randomly or according to a specific rule.

The controller 102 of the second terminal 150 may attempt to detect the face in each of the selected one or more sample images. The controller 102 of the second terminal 150 may detect whether a portion corresponding to a face of a person exists in one image using an open source library such as Open Source Computer Vision (OpenCV) or other commercial programs. The controller 102 of the second terminal 150 may detect whether the portion corresponding to the face exists with respect to each sample image.

FIG. 4 illustrates a sample image selected among the plurality of images included in the stream, according to an embodiment. Also, FIG. 5 illustrates another sample image selected among the plurality of images included in the stream, according to an embodiment. The controller 102 of the second terminal 150 may attempt to detect a face in each of the sample image of FIG. 4 and the sample image of FIG. 5.

Referring to FIG. 3 again, in operation S120, it may be determined that the face has not been detected in at least some of the sample images. The controller 102 of the second terminal 150 may determine whether a portion corresponding to a face exists with respect to each sample image. As the determination result, the controller 102 of the second terminal 150 may determine that the face has not been detected in at least one of the sample images.

For example, the controller 102 of the second terminal 150 may determine that the face has been detected in a sample image corresponding to an upper body of the user of the first terminal 100, like in the image of FIG. 4. On the other hand, the controller 102 of the second terminal 150 may determine that the face has not been detected in a sample image corresponding to a lower body of the user of the first terminal 100, like in the image of FIG. 5.

Referring to FIG. 3 again, in operation S130, image processing may be performed on at least one of the plurality of images included in the stream. When it is determined that the face has not been detected in at least some of the sample images, it may be determined that the plurality of images received from the first terminal 100 include obscene images. For example, when an image such as the image of FIG. 5 is included in the plurality of images received from the first terminal 100, it may be determined that the plurality of images include obscene images.

The controller 102 of the second terminal 150 may perform image processing on at least one of the plurality of images so as to prevent the user of the second terminal 150 from being exposed to the obscene images. The controller 102 of the second terminal 150 may perform image processing on all the plurality of images or some images selected among the plurality of images.

FIG. 6 is a flowchart of operation S130 of performing the image processing, according to an embodiment. Referring to FIG. 6, in operation S131, one or more target images may be selected among the plurality of images included in the stream.

The controller 102 of the second terminal 150 may select one or more target images, on which image processing is to be performed, among the plurality of images. For example, the controller 102 of the second terminal 150 may select all the plurality of images included in the stream as the target images.

According to another embodiment, the controller 102 of the second terminal 150 may perform image processing on one or more images corresponding to the sample image, in which it is determined that the face has not been detected, among the plurality of images. The images corresponding to the sample image may be the entire images received within a specific time range from the time at which the sample image has been received among the plurality of images.

For example, it is assumed that twenty images per second are continuously received through the stream. Also, it is assumed that the most recently received image is selected as a new sample image whenever a period of 4 seconds is returned. Also, it is assumed that it has been determined that the face has not been detected in two sample images. The time when the two sample images have been received may be a time point of 24 seconds and a time point of 32 seconds. The images corresponding to the two sample images may be about eighty images received within a time range from a time point of 22 seconds to a time point of 26 seconds and about eighty images received in a time range from a time point of 30 seconds to a time point of 34 seconds.

A method by which the controller 102 of the second terminal 150 selects the sample image and a method by which the controller 102 of the second terminal 150 selects the target image may be changed according to embodiments. FIG. 7 is a flowchart of operation S110 of attempting to detect the face to operation S131 of selecting the target image, according to an embodiment.

Referring to FIG. 7, in operation S210, one or more sample images corresponding to a recent specific time may be selected among the plurality of images included in the stream. The controller 102 of the second terminal 150 may select one or more sample images among the images received for the recent specific time in the stream.

For example, the controller 102 of the second terminal 150 may select two sample images among images received for the last one second. FIG. 8 is a reference diagram for describing a process of selecting a sample image, according to an embodiment. Referring to FIG. 8, a first image 301 in the stream may have been already selected as a sample image in the past. The controller 102 of the second terminal 150 may additionally select a second image 302 and a third image 303, as the sample image, among images received after a first time point t1 which is a time point before a specific time from a current time.

Referring to FIG. 7 again, in operation S211, the face detection may be attempted in the selected one or more sample images. The controller 102 of the second terminal 150 may detect whether a portion corresponding to a face exists with respect to each selected sample image. For example, the controller 102 of the second terminal 150 may attempt to detect a face in the second image 302 and the third image 303.

In operation S220, it may be determined that the face has not been detected in the selected one or more sample images. The controller 102 of the second terminal 150 may determine that the portion corresponding to the face does not exist in the selected sample images.

When the portion corresponding to the face does not exist in the entire selected sample images, the controller 102 of the second terminal 150 may determine that the face has not been detected. According to another embodiment, when the portion corresponding to the face does not exist in at least one of the selected sample images, the controller 102 of the second terminal 150 may determine that the face has not been detected. For example, the controller 102 of the second terminal 150 may determined that the face has not been detected in the second image 302 and the third image 303.

In operation S231, the entire images corresponding to the recent specific time among the plurality of images included in the stream may be selected as the target images. For example, the controller 102 of the second terminal 150 may select the entire images received for the last one second as the target images. For example, when twenty images per second are continuously received through the stream, the controller 102 of the second terminal 150 may select the about twenty images received for the last one second as the target images. Referring to FIG. 8, the controller 102 of the second terminal 150 may select, as the target images, the entire images (including the second image 302 and the third image 303) received after a time point t1 which is a time point before a specific time from a current time.

FIG. 9 is a flowchart of operation S110 of attempting to detect the face to operation S131 of selecting the target image, according to another embodiment. Referring to FIG. 9, in operation S310, a new sample image may be selected among images newly received in the stream at each specific period. The controller 102 of the second terminal 150 may select one or more new sample images among the entire images received later than the most recently selected sample image at each specific period.

For example, the controller 102 of the second terminal 150 may select two new sample images per second. Referring to FIG. 8, the controller 102 of the second terminal 150 may select, as the new sample images, the second image 302 and the third image 303 among the entire images received later than the first image 301.

Referring to FIG. 9 again, in operation S311, the face detection may be attempted in the new sample image whenever the new sample image is selected. The controller 102 of the second terminal 150 may attempt to detect the face in the newly selected sample image at each specific period.

In operation S320, it may be determined that the face has not been detected in the entire sample images selected within the recent specific time among the sample images. For example, the controller 102 of the second terminal 150 may determine that the face has not been detected in two sample images selected within the last one second. In other words, the controller 102 of the second terminal 150 may determined that the face has not been detected in the second image 302 and the third image 303.

In operation S331, the entire images corresponding to the recent specific time among the plurality of images included in the stream may be selected as the target images. For example, the controller 102 of the second terminal 150 may select the entire images received for the last one second as the target images. For example, when twenty images per second are continuously received through the stream, the controller 102 of the second terminal 150 may select the about twenty images received for the last one second as the target images. Referring to FIG. 8, the controller 102 of the second terminal 150 may select, as the target images, the entire images (including the second image 302 and the third image 303) received after a time point t1 which is a time point before a specific time from a current time.

FIG. 10 is a flowchart of operation S110 of attempting to detect the face to operation S431 of selecting the target image, according to another embodiment. Referring to FIG. 10, in operation S410, the face detection may be attempted in a first sample image selected among the plurality of images included in the stream. The controller 102 of the second terminal 150 may select the first sample image among the plurality of images. The controller 102 of the second terminal 150 may detect whether a portion corresponding to a face exists in the first sample image.

FIG. 11 is a reference diagram for describing a process of selecting a sample image, according to another embodiment. Referring to FIG. 11, a fourth image 311 in the stream may have been already selected as a sample image in the past. The controller 102 of the second terminal 150 may select a fifth image 312 as the first sample image among the images received later than the fourth image 311.

In operation S411, the face defection may be attempted in each of one or more second sample images selected among the entire images received later than the first sample image in the stream. The controller 102 of the second terminal 150 may select one or more second sample images among the images received later than the first sample image. The controller 102 of the second terminal 150 may detect whether a portion corresponding to a face exists in each of the second sample images.

For example, referring to FIG. 11, the controller 102 of the second terminal 150 may select a sixth image 313 as the second sample image among the images received later than the fifth image 312. The controller 102 of the second terminal 150 may detect whether a portion corresponding to a face exists in the sixth image 313.

As another example, the controller 102 of the second terminal 150 may select two images as the second sample images. The two images may include the sixth image 313, and another image received later than the fifth image 312 and received earlier than the sixth image 313. The controller 102 of the second terminal 150 may detect whether a portion corresponding to a face exists in each of the two images.

Referring to FIG. 10 again, in operation S420, it may be determined that the face has not been detected in the first sample image and all the one or more second sample images. The controller 102 of the second terminal 150 may determine that the face has not been detected in the first sample image and the second sample image. For example, the controller 102 of the second terminal 150 may determined that the face has not been detected in the fifth image 312 and the sixth image 313.

In operation S431, the images corresponding to the first sample image and the second sample image among the plurality of images included in the stream may be selected as the target images. The controller 102 of the second terminal 150 may select the images corresponding to the first sample image and the second sample image as the target images.

For example, the images corresponding to the first sample image and the second sample image may include the first sample image and the entire images received later than the first sample image among the plurality of images. Referring to FIG. 11, the controller 102 of the second terminal 150 may select, as the target images, the fifth image 312 and the entire images received later than the fifth image 312.

According to another embodiment, the selected target images may include the first sample image, the one or more second sample images, and neighboring images. The neighboring images may be the entire images received later than the first sample image and received earlier than the last received image among the one or more second sample images. Referring to FIG. 11, the controller 102 of the second terminal 150 may select, as the target images, the fifth image 312, the sixth image 313, and the entire images received later than the fifth image 312 and received earlier than the sixth image 313.

FIG. 12 is a flowchart of operation S110 of attempting to detect the face to operation S131 of selecting the target image, according to another embodiment. Referring to FIG. 12, in operation S510, two or more sample images may be selected among the plurality of images included in the stream, wherein the two or more sample images include a first sample image corresponding to a first time point and a second sample image corresponding to a second time point having a time difference from the first time point by a specific time or more.

The controller 102 of the second terminal 150 may select the first sample image among the plurality of images included in the stream. The time at which the first sample image has been received may be the first time point. The controller 102 of the second terminal 150 may select, as the second sample image, an image received after elapse of more than a specific time from the time at which the first sample image has been received. In other words, the time difference between the time at which the first sample image has been received and the time at which the second sample image has been received may be more than the specific time. The specific time may be, for example, one second.

Also, the controller 102 of the second terminal 150 may additionally select a sample image among the images received earlier than the first sample image. Also, the controller 102 of the second terminal 150 may additionally select a sample image among the images received later than the first sample image and received earlier than the second sample image. Also, the controller 102 of the second terminal 150 may additionally select a sample image among the images received later than the second sample image.

For example, referring to FIG. 11, the controller 102 of the second terminal 150 may select, as the first sample image, an image received at an arbitrary second time point t2 in the stream. The controller 102 of the second terminal 150 may select, as the second sample image, an image received at a third time point t3 among the images received after elapse of more than one second from the second time point t2.

The controller 102 of the second terminal 150 may additionally select a fourth image 311 as the sample image among the images received earlier than the second time point t2. The controller 102 of the second terminal 150 may additionally select a fifth image 312 and a sixth image 313 as the sample images among the images received later than the second time point t2 and received earlier than the third time point t3. The controller 102 of the second terminal 150 may additionally select a seventh image 314 as the sample image among the images received later than the third time point t3.

Referring to FIG. 12 again, in operation S511, the face detection may be attempted in each of the selected two or more sample images. The controller 102 of the second terminal 150 may attempt to detect the face in the first sample image, the second sample image, and all the additionally selected sample images.

In operation S520, it may be determined that the face has not been detected in the first sample image, the second sample image, and the entire sample images corresponding to the time from the first time point to the second time point among the selected two or more sample images. The controller 102 of the second terminal 150 may determine that the face has not been detected in the first sample image received at the second time point t2. Also, the controller 102 of the second terminal 150 may determine that a portion corresponding to a face has not been detected in the second sample image received at the third time point t3. Also, the controller 102 of the second terminal 150 may determine that the face has not been detected in the fifth image 312 and the sixth image 313 selected as the sample images among the images received later than the second time point t2 and received earlier than the third time point t3. In other words, the controller 102 of the second terminal 150 may determined that the face has not been detected in the sample images received from the second time point t2 to the third time point t3 among the selected entire sample images.

In operation S531, the entire images corresponding to the time from the first time point to the second time point among the plurality of images included in the stream may be selected as the target images. For example, the controller 102 of the second terminal 150 may select, as the target images, the entire images received for the time from the second time point t2 to the third time point t3. The selected target images may include the first sample image, the second sample image, and the sample images received later than the second time point t2 and received earlier than the third time point t3. Also, the selected target images may include all the remaining images, which are not selected as the sample images, among the entire images received later than the second time point t2 and received earlier than the third time point t3 in the stream.

Referring to FIG. 6 again, after operation S131 of selecting the target images, operation S132 of selecting al target region of at least a portion of each of the target images. FIG. 13 is a reference diagram illustrating a selected target region according to an embodiment. As illustrated in FIG. 13, the controller 102 of the second terminal 150 may select the entire region of each of the target images as the target region.

According to another embodiment, the controller 102 of the second terminal 150 may select, as the target region, a region corresponding to a skin color in each of the target images. The controller 102 of the second terminal 150 may detect the region corresponding to the skin color in each of the target images. The skin color may indicate at least one color. Since each person has a different skin color, the controller 102 of the second terminal 150 may detect regions corresponding to various skin colors.

FIG. 14 is a reference diagram illustrating a selected target region according to another embodiment. As illustrated in FIG. 14, the controller 102 of the second terminal 150 may select a region having a skin color in a target image as the target region. In other words, each pixel included in the selected target region may have a skin color.

The controller 102 of the second terminal 150 may select one or more closed curves in each of the target images as the target region. For example, unlike in FIG. 14, the region having the skin color may include a plurality of closed curves adjacent to or spaced apart from each other The controller 102 of the second terminal 150 may select the entire closed curves as the target region. According to another embodiment, the controller 102 of the second terminal 150 may select, as the target region, one or more closed curves having the largest area among the plurality of closed curves.

FIG. 15 is a reference diagram illustrating a selected target region according to another embodiment. As illustrated in FIG. 15, the controller 102 of the second terminal 150 may select, as the target image, a rectangular region including a region having a skin color in the target image. According to another embodiment, the controller 102 of the second terminal 150 may select, as the target image, a circular, oval, or polygonal region including the region having the skin color, instead of the rectangular region.

The controller 102 of the second terminal 150 may select one or more polygonal regions in each target image as the target region. For example, unlike in FIG. 15, the region having the skin color may include a plurality of closed curves adjacent to or spaced apart from each other The controller 102 of the second terminal 150 may select one polygonal region including the entire closed curves as the target region. According to another embodiment, the controller 102 of the second terminal 150 may select a plurality of polygonal regions as the target region. Each of the polygonal regions may include at least one of the plurality of closed curves. According to another embodiment, the controller 102 of the second terminal 150 may select, as the target region, one or more polygonal regions including one or more closed curves having the largest area among the plurality of closed curves.

Referring to FIG. 6 again, in operation S133, the image processing may be performed on the selected target region of each of the target images. FIG. 16 illustrates an image, on which the image processing has been performed, according to an embodiment. As illustrated in FIG. 16, the controller 102 of the second terminal 150 may delete the selected target region in the target image, like in FIG. 15.

FIG. 17 illustrates an image, on which the image processing has been performed, according to another embodiment. As another example, as illustrated in FIG. 17, the controller 102 of the second terminal 150 may apply a blur effect to the target region. FIG. 18 illustrates an image, on which the image processing has been performed, according to another embodiment. As another example, as illustrated in FIG. 18, the controller 102 of the second terminal 150 may apply a mosaic effect to the target region. FIG. 19 illustrates an image, on which the image processing has been performed, according to another embodiment. As another example, as illustrated in FIG. 19, the controller 102 of the second terminal 150 may substitute the target region with another image.

As another example, the controller 102 of the second terminal 150 may adjust a color, a brightness, a contrast, or a saturation of the target region. Also, the controller 102 of the second terminal 150 may combine the image processings listed above. For example, the controller 102 of the second terminal 150 may apply the blur effect on the target region, reduce the saturation, and reduce the contrast.

Referring to FIG. 3 again, in operation S140, the plurality of images included in the stream may be displayed. The output interface 105 of the second terminal 150 may display the plurality of images. For example, the display included in the output interface 105 of the second terminal 150 may continuously display twenty images per second. The plurality of images may include one or more images on which the image processing has been performed by the controller 102 of the second terminal 150.

Therefore, the user of the second terminal 150, who makes a video call with the user of the first terminal 100, can be prevented from being exposed to obscene images from the counterpart. Also, the user of the second terminal 150 can be prevented from sexual shame or discomfort that he or she may feel from the image from the counterpart. Also, a proper video call between the user of the first terminal 100 and the user of the second terminal 150 may be guided.

In operation S150, a request for cancelling the image processing may be received. For example, the user of the second terminal 150 may want to view the original of the received image, while taking the exposure to inappropriate images lying down. The display included in the output interface 105 of the second terminal 150 may output a message asking whether to cancel the image processing. For example, the output interface 105 of the second terminal 150 may output a message “No face is detected. Please press the button to view the original.” The user of the second terminal 150 may press the button included in the input interface 101 of the second terminal 150 as a response to the message. In other words, the input interface 101 of the second terminal 150 may receive the request for cancelling the image processing from the user of the second terminal 150.

In operation S160, the image received after the reception of the request among the plurality of images included in the stream may be displayed without image processing. The controller 102 of the second terminal 150 may determine that the face has not been detected in the image received after the reception of the request. In spite of the above determination, the controller 102 of the second terminal 150 may not perform image processing on the image received after the reception of the request. The controller 102 of the second terminal 150 may display one or more images received after the reception of the request without image processing.

FIG. 20 is a flowchart of an image display method according to another embodiment. Referring to FIG. 20, in operation S600, a video call session with the first terminal 100 may be established. The communication interface 104 of the second terminal 150 may establish the video call session with the first terminal 100.

In operation S610, a stream including a plurality of images captured by the first terminal 100 may be received through the video call session. The communication interface 104 of the second terminal 150 may receive the stream from the first terminal 100 through the video call session. The stream may include a plurality of images.

In operation S620, the plurality of images included in the stream may be displayed. The output interface 105 of the second terminal 150 may display the plurality of received images.

In operation S630, face detection is attempted in each of one or more sample images selected among the plurality of images included in the stream. The controller 102 of the second terminal 150 may select at least one of the plurality of images. The controller 102 of the second terminal 150 may detect whether a portion corresponding to a face exists in each selected sample image.

In operation S640, it may be determined that the face has not been detected in at least some of the sample images. The controller 102 of the second terminal 150 may determine that the face has not been detected in one or more sample images. When the face has not be detected in the sample image, inappropriate images may be included in the plurality of images.

In operation S650, the video call session may be terminated. The communication interface 104 of the second terminal 150 may terminate the video call session with the first terminal 100. Therefore, the user of the second terminal 150, who makes a video call with the user of the first terminal 100, can be prevented from being exposed to inappropriate images from the counterpart.

According to the embodiments set forth above, it is possible to prevent the user who makes the video call with the counterpart from being exposed to obscene images from the counterpart. Also, it is possible to prevent the user who makes the video call with the counterpart from sexual shame or discomfort that he or she may feel from the image from the counterpart. Also, it is possible to guide a proper video call between the users.

Logical blocks, modules or units described in connection with embodiments disclosed herein can be implemented or performed by a computing device having at least one processor, at least one memory and at least one communication interface. The elements of a method, process, or algorithm described in connection with embodiments disclosed herein can be embodied directly in hardware, in a software module executed by at least one processor, or in a combination of the two. Computer-executable instructions for implementing a method, process, or algorithm described in connection with embodiments disclosed herein can be stored in a non-transitory computer readable storage medium.

Embodiments may be embodied in a non-transitory computer-readable recording medium having recorded thereon computer-executable instruction codes, such as a program module executable by the computer. The non-transitory computer-readable recording medium may be any available medium which can be accessed by the computer and may include any volatile and non-volatile media and any removable and non-removable media.

Furthermore, the non-transitory computer-readable recording medium may include any computer storage medium and communication medium. The computer storage medium may include any volatile and non-volatile media or any removable and non-removable media embodied by a certain method or technology for storing information such as computer-readable instruction codes, a data structure, a program module, or other data. The communication medium may include computer-readable instruction code, a data structure, a program module, other data of modulated data signals, or other transmission mechanisms, and may include any information transmission medium.

It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments.

While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims. 

What is claimed is:
 1. A method of a video call, the method comprising: receiving, by a first mobile terminal, a video stream from a second mobile terminal with which the first mobile terminal has established a video call session; displaying, on a display of the first mobile terminal, a series of images of the video stream during the video call session; processing, by the first mobile terminal, at least part of the series of images to determine whether a human face is contained therein; and further processing, by the first mobile terminal, to display the series of images such that: (1) when it is determined, by the first mobile terminal, that a human face of a user is contained in a first one of the series of images, the first mobile terminal displays the first image on the display, (2) when it is determined, by the first mobile terminal, that the human face of the user is not contained while a body part of the user is contained in a second one of the series of images that is received subsequent to the first image, the first mobile terminal applies a first visual effect to the second image to prevent the body part of the user from being exposed when displaying the second image, (3) when it is determined, by the first mobile terminal, that the human face of the user is still not contained while the body part of the user is contained in a third one of the series of images that is subsequent to the second image, the first mobile terminal applies the first visual effect to the third image to prevent the body part of the user from being exposed when displaying the third image, and (4) when it is determined, by the first mobile terminal, that the human face of the user is contained in a forth one of the series of images that is subsequent to the third image, the first mobile terminal displays the forth image without applying the first visual effect thereto.
 2. The method of claim 1, wherein the first mobile terminal analyzes the first image to determine a skin color of the human face, wherein the first mobile terminal applies the first visual effect on an area of the second image containing the skin color.
 3. The method of claim 1, wherein the first visual effect comprises at least one selected from a group consisting of a blur effect, a mosaic effect, substituting with another image, and adjusting of color, brightness, contrast, or saturation.
 4. A non-transitory computer-readable recording medium having recorded thereon a program for executing the method of claim
 1. 